FERNALD, — ALNUS. 25 
* Mature strobiles 2 cm. or more long (rarely shorter in A. oblongifolia and A. 
glabrata). 
+ Petioles pubescent. 
+ Leaves ovate to obovate, rounded at base. 
A. acuminata, HBK. Bark of branches ashy brown, smooth: buds 
pubescent: leaves short-acuminate, finely and doubly serrate-dentate, 
0.5 to 1.5 dm. long, 0.4 to 1 dm. broad, subcoriaceous, sparingly pilose 
on the midrib above, more abundantly so on the midrib and nerves 
beneath; petiole about 1 to 1.5 em. long: peduncles stout, glabrous or 
minutely puberulent: staminate aments becoming 1 dm. or more long; the 
ashy-brown strobiles 3 or 4, sessile or short-pedicelled, ovoid-oblong, 2.2 to 
2.6 cm. long, about 1.5 cm. thick: nutlet lanceolate, 4 mm. long, 1.75 
mm. broad, bordered by an equally broad coriaceous wing. — Nov. 
Gen. & Sp. ii. 20; Regel in DC. Prodr. xvi, pt. 2, 183. Described 
from the Andes of Peru, this species has been made to include practically 
all the forms of South America, Mexico, California and New Mexico. 
From the original description, however, the species appears to be a well 
marked plant represented in the Gray Herbarium from Guatemala and 
Bolivia. GuaTEMALA, San Lucas, Dept. Zacatepequez, alt. 1700 m., 
April, 1890 (/. D. Smith, no. 2188): Boxtvia (Bang, no. 1893). 
++ ++ Leaves oblong-lanceolate or elliptic, subcuneate at base. 
A. oblongifolia, Torr. Bark of branches reddish brown, smooth ; 
of the branchlets puberulous or glabrate: buds glabrous: leaves acute, 
sharply double-serrate, 0.5 to 1.5 cm. long, 3 to 6.5 cm. broad, more or 
less glandular-dotted, coriaceous, pilose or glabrate above, paler and 
more or less pilose on the prominent veins beneath ; petioles slender, 
1 to 2.5 cm. long: peduncles puberulent or glabrate: staminate aments 
becoming 1 dm. long; the brown or slightly ferrugineons strobiles 3 to 5, 
pedicelled, sub-cylindric, when mature about 2 cm. long, 1 cm. thick: 
nutlet obovate, 3 mm. long, 2 mm. broad, with a narrow submembra- 
naceous wing. — Bot. Mex. Bound. 204. A. serrulata, y oblongifolia, 
Regel, 1. c. 188. A. acuminata, Sargent, Silva, ix. 79, t. 457, in part, 
not HBK. —New Mexico, banks of the Mimbres and near Santa Bar- 
bara, tree 9.23 m. high (Charles Wright, no. 1864): Catirornia, San 
Bernardino, “tree 80 feet high, 2-3 feet in diameter,” 1876 (C. C. 
J. G. Lemmon). Sonora, Huchuerachi, alt. 1230 m., Dec., 
1890 (C. V. Hartman, no. 322, F. HL. Lloyd, no. 464). 
